Exhaust manifold bolts frozen

[bobs600honda]

attempting to remove Exhaust
manifold but bolts from manifold to heat exchanger are frozen.
Top most bolt has broken off - middle bolt is not budging (nut or bolt) and not sure how to access bottom bolt...
Any ideas  - tips - get out the dremel and have at it?
Thanks in advance.
Bob
Tracy

[Bill]

Freeze Off by CRC has done the trick for me – spray and tap with a small hammer to loosen and crack the rust.   Also drilling the bolt out.  And, knocking the head of the bolt off and then you have more meat on the bolt when the part comes apart.  Then Vice Grips go to work.
http://www.amazon.com/CRC-05002-Freeze- ... op?ie=UTF8

[bobs600honda]

Thanks, I will give that a try.